ASSP is a mail proxy aiming towards fighting spam. This page covers how I installed ASSP onto my system and set it up.

My main interest is to have SRS/SPF running, sadly postfix still has no support for that.

After installing ASSP initial configuration can be done by starting it, and browsing to port 55555 on the machine running it. As my server has iptables running, I achieved accessibility using an SSH tunnel:

% ssh -L 55555:localhost:55555 my.server.tld

BEWARE: the admin interface heavily uses javascript, without it configuration is a PITA. So if there is a very long page with a non-working navigation bar, maybe Firefox's NoScript plugin is active.

First, a new service has to be registered inside /etc/services for an internal-only running MTA. My services file already included an entry for “any private mail system” on port 24, just had to uncomment it. This is the port postfix will listen on, being fed with mails from ASSP which is designed for being the entry point of mail processing and therefore listening on port 25 of the external IP.

Next step is to change Postfix's listen port, which is done inside master.cf:

smtp      inet  n       -       n       -       -       smtpd

has to be changed into:

private   inet  n       -       n       -       -       smtpd

private has to match the name of the newly created service in /etc/services.

• ASSP Wiki
• ASSP Documentation about Postfix